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761.
Sang-Wook Park Jihoon Kim Jong-Lyul Park Ji-Yun Ko Ilkyun Im Hyo-Sang Do Hyemin Kim Ngoc-Tung Tran Sang-Hun Lee Yong Sung Kim Yee Sook Cho Dong Ryul Lee Yong-Mahn Han 《Biochemical and biophysical research communications》2014
Genomic imprinting is an epigenetic phenomenon by which a subset of genes is asymmetrically expressed in a parent-of-origin manner. However, little is known regarding the epigenetic behaviors of imprinted genes during human development. Here, we show dynamic epigenetic changes in imprinted genes in hESCs during in vitro differentiation into specialized cell types. Out of 9 imprinted genes with single nucleotide polymorphisms, mono-allelic expression for three imprinted genes (H19, KCNQ1OT1, and IPW), and bi- or partial-allelic expression for three imprinted genes (OSBPL5, PPP1R9A, and RTL1) were stably retained in H9-hESCs throughout differentiation, representing imprinting stability. Three imprinted genes (KCNK9, ATP10A, and SLC22A3) showed a loss and a gain of imprinting in a lineage-specific manner during differentiation. Changes in allelic expression of imprinted genes were observed in another hESC line during in vitro differentiation. These findings indicate that the allelic expression of imprinted genes may be vulnerable in a lineage-specific manner in human pluripotent stem cells during differentiation. 相似文献
762.
Solution structures and model membrane interactions of Ctriporin,an anti‐methicillin‐resistant Staphylococcus aureus Peptide from Scorpion Venom
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Susmita Bandyopadhyay Ryan Loh Junjie Brendan Lim R. Sanjeev Woon Yong Xin Chong Kok Yee Sim Ming Hui Melodies Nicole Yow J. Sivaraman Chiradip Chatterjee 《Biopolymers》2014,101(12):1143-1153
Ctriporin peptide (Ctr), a novel antimicrobial peptide isolated from the venom of the scorpion Chaerilus tricostatus, shows a broad‐spectrum of antimicrobial activity and is able to inhibit antibiotic resistant pathogens, including Methicillin resistant Staphylococcus aureus, Methicillin Resistant Coagulase‐negative Staphylococcus, and Penicillin Resistant Staphylococcus epidermidis strains. To understand the active conformation of the Ctr peptide in membranes, we have investigated the interaction of Ctr with the negatively charged and zwitterionic membrane‐mimetic micelles such as sodium dodecyl sulphate (SDS) and n‐dodecylphosphocholine (DPC), respectively. The interactions were studied using fluorescence and circular dichroism (CD) spectroscopy. Fluorescence experiments revealed that the N‐terminus tryptophan residue of Ctr interacted with the hydrophobic core of the membrane mimicking micelles. The CD results suggest that interactions with membrane‐mimetic micelles induce an α‐helix conformation in Ctr. Moreover, we have determined the solution structures of Ctr in SDS and DPC micelles using nuclear magnetic resonance (NMR) spectroscopy. The structural comparison of Ctr in the presence of SDS and DPC micelles showed significant conformational changes. The observed structural differences of Ctr in anionic versus zwitterionic membrane‐mimetic micelles suggest that the mode of interaction of this peptide may be different in two environments which may account for its ability to differentiate bacterial and eukaryotic cell membrane. © 2014 Wiley Periodicals, Inc. Biopolymers 101: 1143–1153, 2014. 相似文献
763.
Wilson Thau Lym Yong Siew Hoo Ting Yoong Soon Yong Vun Yee Thien Siew Hie Wong Wei Lie Chin Kenneth Francis Rodrigues Ann Anton 《Journal of applied phycology》2014,26(3):1597-1606
Cultivation of seaweeds on a commercial scale requires a large number of propagules with desirable phenotypic traits which include high growth rates and resistance to diseases. Seaweed micropropagation can be considered as one of the best methods to provide a large amount of seedlings for commercial cultivation. This study was carried out to optimize the parameters known to affect the growth of Kappaphycus alvarezii in vitro and subsequently improve the production of seedlings through micropropagation. Suitability of media, concentration of phytoregulators, types and concentration of fertilizers, culture density, light intensity, interval of aeration activity, salinity, and pH were found to be critical factors for the growth of K. alvarezii. The optimum condition for direct regeneration of K. alvarezii in a culture vessel was found to be cultivation of explants in Provasoli's enriched seawater (PES) media supplemented with 2.5 mg L?1 6-benzylaminopurine (BAP), 1.0 mg L?1 indole-3-acetic acid (IAA), and 3.0 mg L?1 natural seaweed extract (NSE) with culture density of 0.4 %?w/v, under light intensity of 75 μmol photons m?2 s?1, continuous aeration of 30.0 L h?1, salinity of 30.0 ppt, and pH 7.5. An airlift photobioreactor was constructed for the mass propagation of K. alvarezii explants with optimum culture conditions obtained from the study. The optimum growth rates of the K. alvarezii explants in culture vessels (5.5 % day?1) and photobioreactor (6.5 % day?1) were found to be higher than the growth rate observed in field trials in the open sea (3.5 % day?1). The information compiled during the course of this study will be of utility to commercial seaweed cultivators. 相似文献
764.
765.
Mikael Hanninen Romain Cassagneau Jaimie Manlucu Raymond Yee 《Indian pacing and electrophysiology journal》2014,14(3):150-151
Lead extraction is becoming increasingly common as indications for pacing and ICD insertion expand. Periop management varies between extraction centers, and no clinical guidelines have addressed the need for perioperative anticoagulation. We report a case of massive thrombosis which occurred shortly after laser lead extraction and is undoubtedly related to the trauma of the extraction and ensuing hypercoagulabiilty. Routine post-operative anticoagulation has been advocated as a means to prevent access vein (subclavian) stenosis, but many centres do not employ a routine post-extraction anticoagulation strategy. Pulmonary embolism following lead extraction is a known complication of this procedure and late mortality following lead extraction is a significant and underappreciated problem. We propose that further research attention should be directed at addressing the issue of routine post-extraction anticoagulation. 相似文献
766.
Saiyong Zhu Rajesh Ambasudhan Woong Sun Hyun Jung Kim Maria Talantova Xiaojing Wang Mingliang Zhang Yu Zhang Timothy Laurent James Parker Han-Seop Kim Jeffrey D Zaremba Sofiyan Saleem Sara Sanz-Blasco Eliezer Masliah Scott R McKercher Yee Sook Cho Stuart A Lipton Janghwan Kim Sheng Ding 《Cell research》2014,24(1):126-129
767.
CS Ortiz 《Biotechnic & histochemistry》2014,89(2):121-125
A simple low pressure liquid chromatographic method is reported that can separate the basic fuchsine homologues, rosaniline, magenta II and new fuchsine from an impure commercial dye. The chromatographic purity of the separated dyes is > 90%. All homologues were obtained in multi-milligram amounts per chromatographic run; precise yields depend on the composition of the starting material and potentially may be greater. This is a useful preparative procedure for generating chromatographically pure samples of basic fuchsine homologues, especially those that cannot be obtained in pure form by direct synthesis. 相似文献
768.
769.
770.
Seung Yeub Song Eun Yee Jie Myung Suk Ahn In Ho Lee Ill-Sup Nou Byung Whan Min Suk Weon Kim 《Molecular breeding : new strategies in plant improvement》2014,33(2):453-464
Fourier transform infrared spectroscopy (FT-IR) spectroscopy in combination with multivariate analysis was used to discriminate two different F1 hybrid lines from their parental inbred lines. Genomic DNA was isolated from leaves of three parental lines and two F1 hybrid lines of Brassica campestris subsp. pekinensis. Purified genomic DNA was analyzed by FT-IR spectroscopy in the spectral region from 4,000 to 400 cm?1. FT-IR spectra confirmed typical spectral differences between the frequency regions of N–H stretching (amide I) and C=O stretching vibrations (amide II) as well as PO2 ? ionized asymmetric and symmetric stretching. Principal component analysis was able to discriminate between F1 hybrid progenies depending on their parental lineages, even though they share the same maternal background. Partial least squares discriminant analysis gave a more clear discrimination between the two parental lines and their hybrid progenies. These FT-IR spectral differences might be directly related to subtle changes in the base functional group and backbone structures of genomic DNA. Considering these results, this technique could provide a solid research foundation for FT-IR spectral-based rapid diagnosis, selection, and discrimination of parental lines from their progenies. Furthermore, this technique could be applied to test purity in the hybrid seed industry. 相似文献